Wide range governor for diesel engines



May 6, 1941. N. M. MccuLLoUGH 2,241,096

WIDE RANGE GOVERNOR FOR DIESEL ENGINES Filed Dec. 24, 1937 s sneets-shet1 Allyn/Aix 1U. 5541i 16.45 j 45" INVENTOR. /Vfa N, N ff'uzLoz/m,

ATTORNEYS.

May 6, 1941. N. M. MccULLoUGH 2,241,096

WIDE RANGE GOVERNOR FOR DIESEL ENGINES Filed Dec. 24, 1957 ssheets-sheet z INVENTOR. /Vfn M. Mff'aa aaa/1.

ATTORNEYS.

Patented May 6, 1941 PATENT YCFFICE WIDE RANGE GOVERNOR FOR DIESELENGINES Neel M. McCullough, Anderson, Ind., assignor to The PierceGovernor Company, Anderson, Ind.,

a corporation Application December 24, 1937, Serial No. 181,680

17 Claims.

This invention relates to a governor which is peculiarly effective whenassociated with a Diesel engine fuel supply for the regulation thereof.

The chief object of this invention is to provide a governor structurewhich will regulate the fuel supply to a Diesel engine in thecharacteristic manner which an ordinary centrifugal governor wouldoperate, and in addition thereto, compensates automatically for thetendency of the engine, due to the inherent fuel pump characterfistics., to overspeed at slow idle running.

The invention is associated, for example only, with a Bosch fuel pumpsuch as more or less diagrammatically illustrated in the CommercialMotor, pp. 627 for December, 1935, or a similar device, which fuel pumphas the following mentioned characteristics. At slow idle speed, the

Diesel engine will gradually increase its speed until the same maybecome excessive anddangerous. This results from the following: Fuelpumps of this general character include a fuel supply piston that isreciprocated at the same or at a speed proportional tothe engine speedand the fuel supply is regulated usually by sim'ultaneously'varying allthe intake intervals or the exhaust intervals or the pump stroke incertain special cases. These fuel pumps thus have a common actuatingmember and in the t'wo former instances, this is called the rack bar.

The pump piston has a predetermined operative clearance in the cylinderso that at each reciprocation there is some leakage. When the piston ofthe fuel pump for the Diesel engineit being understood there is usuallyone fuel pump piston per engine cylinderhas a relatively high rate ofreciprocation, the effective leakage is relatively small comparativelybetween the piston and cylinder of the pum-p. At slow speeds, however,the leakage therebetween'is proportionally greater. At very slow speedssuch leakage may become quite excessive in proportion to the total fuelrequired for slow or low idle engine operation with the result that agoverned engine will progressively increase its speed until finally itmay run away.

The chief object of the present governor, therefore, is, when associatedwith fuel pumps of the aforesaid general character, to prevent thisoverspeeding or running away when operating at low idle.

'Anordinary governor has a spring which is normally imposed as load on amechanism which is centrifugally operable. .Due to this peculiarity ofthe Diesel pump of the character set forth. such a vgovernor in order toprevent this over- 1() is relatively small.

50 from spring loading.

5 The present invention, therefore, provides a compensating or auxiliaryspring. Since at slow speed'idle position. the speed of vthe engine isrelatively slow initially,`-the centrifugal force exerted on theoperativefmembers of the governor Wherefore, the auxiliary springstructure, before mentioned, is of a lesser force than the main loadspring first mentioned and in a direction the same as the main loadspring. Since this centrifugal force at this period of control isrelatively small, if the main load spring were then effective, saidcentrifugal force would be ineffective for v4control purposes.Wherefore, the mechanism including both springs is so 'arranged thatfrom wide open pump position to gut high idle position, the main loadspring is operative only and the auxiliary spring is ineffective, andfrom the high idle speed toward the slow idle speed the main load springis effective for the major portion of thisf-range of operation and withthe auxiliary spring still ineffective but as the operation approachesthe slow idle speed the main load spring becomes ineffective andimmediately the auxiliary spring becomes effective and remains in effectduring the remainder of the operation toward and during slow idle speed.

With this invention, better regulation than that of the conventionalgovernor has been obtained and it is possible to hold this closeregulation for a wider range of governor speed so that the performanceof the invention has produced amazing results, due. consideration beinggiven to the normal operating characteristics of the Diesel fuel pumpfrom slow idle to high idle speeds as well as from light load to fullload operation.

the major portion of its range from the remote speed limit towards theVcommon speed limit is operative while the other spring is sov operativeand substantially at no time isthere an intervening period during whichthe governor is free This arrangement is .ibtained vby"connecting thesprings to one of the levers so that the connections are not in thealignment with the other and the axis of the connected lever.

5'5 Another feature of the'invention consists in connecting said springsto this lever so that the spring connections have different lineararcuate travel and operate through diilerent effective leverages. Thisarrangement permits relatively close regulation from full load to highgoverned idle engine operation. The result is a governor which is moreeiective during all periods of operation from slow idle to and includingthe m'aximum speed for which the governor is adjusted.

Another object of this invention is to provide an arrangement of leversand main or load and auxiliary springs embodying the basic featuresabove mentioned and adapting the same so lthat the main load springassociated with the throttlel may be arranged whereby manual footcontrol is possible without undue strain upon the operator. This featureis of particular value when the governed Diesel engine is embodied in amotor vehicle which .is foot throttle controlled.

The chief feature of this embodiment of the invention is the addition ofan auxiliary arm of elongated character and the elongation of thethrottle lever together with a multiplying linkage arrangement.

A further object of the invention consists in the provision of means forstopping the engine by moving the fuel pump rack shaft to closedposition through a device incorporated as an' integral part of the rstmentioned governor structure, or as an additional means which may beseparate from thegovernor or be applied the same and the rack shaft.Herein I3 indicates a housing in which is mounted a centrifugallyoperable device, similar or identical to that shown dotted in Figs. 4and 6, which is driven by shaft I4 through gear I5 meshing with a geardriven by the engine at engine speed or at a speed proportional thereto.

The housing I3 is suitably mounted upon the engine (preferably) and injuxtaposition to the fuel pump for operation by the former and forcontrolling the latter.

Housing I3a is suitably secured by means not shown, to housing I3 andsupports cover I3b se.

cured by bolts I5a at I4a. Housing I3a has 'boss I6 with a boretherethrough that supports shaft I1. Manual control lever I8 is securedto the exposed end of the shaft as at I8a, see Fig. 2.

'Ihe speed responsive device includes a shaft I9, see Figs. 1 and 2,that extends from housing I3 into housing I3a. Lever 20 is secured toshaft I9. It includes three offset boss portions 2|, 22 and 23-see Fig.l-and terminates in a slotted end 24 straddling link 25 to which it ispinned as at 26. Link 25 includes an opposite slotted end 25a whichstraddles the adjacent end of the rack bar II or pump control rod or anextension thereof and .to which it is pivotally secured as at 21. Thus,the rack bar is responsive to movement of lever 20. 'Ihis lever ismovable in response to the variation in engine speed and as otherwisemodied by the mechanism now to be described,

being broken away and shown in section to illus#- trate the spring andlever system thereof in greater detail, the section being taken on lineI-I of Fig. 42 and in the direction of the arrows.

Fig. 2 is an end elevational view of the governor shown in Fig. 1, partsbeing broken away and shown in section, the same being taken on line 2-2of Fig. 3 and in the direction of the arrows.

Fig. 3 is a top plan View of the governor shown in Figs. 1 and 2.

Fig. 4 is a side elevational view similar to Fig. 1 but not sectionedand of a modified form of governor.

Fig. 5 is an end elevational view, similar to Fig. 2 but notsectionedand of the form of the governor shown in Fig. 4.

Fig. 6 is an end elevational view taken from the opposite side of thegovernor, reference being had to Fig. 5.

Fig. 7 is a view similarto Fig. 4 of a form of the invention similar toFig. 1, the fuel Pump being omitted and centrifugal operable portions ofthe governor being concealedy in the governor housing.

Fig. 8 is a sectional view taken at right angles to Fig. 'I and of theleft hand portion `of the invention shown therein.

In Figs. 1 to 3 of the drawings there is illustrated one embodiment ofthe invention. In Fig. 1, I0 indicates a Diesel engine fuel pump struc-'.ture generally as before identified, having the pump control ar rackshaft Il and fuel supply discharges I2 which connect each to a cylinderof the governed Diesel engin( The governor includes a speed responsivepower arrangement, and operative connections between which is that partoi' the invention that produces the remarkable control results obtainedand herein previously briefly set forth.

Rigid with shaft I1 is arm 28 which includes two oiset portions 29 and30 and an apertured end 3l. Boss 2l on lever 20 is apertured. A spring32 has an elongated open loop 32a which is mounted in groove 33a on pin33-carried by portion 29. The other end of the spring' 32 is connectedto an eyebolt 34 having an adjustable but rigid connection with oisetportion 2| and secured in such position Iby nuts 35.

Offset portion 30 of, arm 28 is apertured at 30a and therein ispivotally secured angular end 35 of rod 31 and retained by washers 38and cotter key 39,.see Fig. 2. The other end of rod 31 is slidablymounted in the apertured boss 23 on lever 20, see Fig. 1. Astop collar40 is rigidly secured in adjusted position on rod 31 by set screw 4I.

An leyebolt 42 is rigidly and adjustably secured by nuts 43 to theapertured end 3l of arm 28. Spring 44 has one end connected to thisbolt. The other end of the spring is secured to member 45 slidablysupported in boss 22 and terminating in the stop or head 46.

In the foregoing structure, spring 44 constirtutes the main load spring,and spring 32 the minor or auxiliary spring. The former is effective onthe lever 20 from a speed below high idle but above low .idle to allother load operating speeds. The latter is effective at low idle speedand for a short range toward high idle speed.

Thus, each spring is adiustably but relatively idle, no control could beobtained because it has been determined that at low idle speed, the fuelpump must Isupply more fuel than at high idle usual effectiveness, dueto the aforesaid condition, it is arranged to become ineffective andjustment being xed by nut 12. Lever 13 is pivminor spring 32 is arrangedto become effective from that speed down to and including low idlespeed.

The use of this minor spring makes the governor selectively responsiveto speed variations and when adjusted both initially or duringoperation, permits closer control over the Diesel engine.

The initial control is obtained by the eyebolts l and collar 40. Themanual control is obtained by lever I8 secured to shaft I1. Anadjustable stop for said lever, see Fig. 3, includes an offset ann |8bon said lever which mounts a stop bolt 46 locked by nuts 41.

'Ihe lever I8 constitutes a manual control for varying the control toinsure governor maintentially vertical, it is in the slow or low idleposition4 and when in the inclined position corresponding to the dottedposition of arm 28, it is in the load speed position. Stop 46, adaptedto engage housing I3, is the high speed adjustment stop. 1 :i

Note that spring 32 at end 33a has lost motion movement relative toanchorage 33 and that spring 44 through member 45 has similar movementrelative to anchorage, 22..'l This provides for the transition necessaryto transfer the governor operation-from the minor spring to the loadspring and vice versa.

In Figs. 4 to 6, there is illustrated another embodiment of theinvention. In Fig. 4, 58 indicates a fuel pump device for a Dieselengine and having a control member or rack bar 5| and outlets 52, onefor each cylinder of the engine and supplying a measured amount of fuelto each.

1n Figs. 4to 6, 53 indicates a housing into which extends shaft 54carrying on its exposed end a gear 55 adapted to be driven by the engineat a speed proportional thereto. Within the housing 53 the shaft 54 isprovided with a collar 56 which pivotally supports at 51 the weight arms58 having weighted end portions 59 recessed at 59a to straddle the shaftand the sleeve 68 slidably supported thereby.4 The arms 58 have portions6| adapted to engage collar 68a on said sleeve. As shaft 54 increasesits rotational speed,

the Weights move outwardly from the shaft axis and the portions 6Ielevate sleeve 68.

Sleeve 68 terminates in an anti-friction collar structure 62 againstwhich bears in diametrical relation portions 63 of a bifurcated member64 rigid with shaft 65. Exteriorly of housing 53 and rigid with shaft 65is arm 66. Also pivotally secured at 61a is an arm 61. These arms arelink connected as at 68. t

A bracket 69 is suitably secured as at 69a to housing 53. It includesoffset portion 18 which adjustably mounts the high speed stop 1|, theadotally supported on the bracket 69 at 14 and other end being securedto arm 61 at 18. TheV eyes may be ofsuiiicient size to provide for someplay or lost motion, if desired and as illustrated.

Load Spring 19 has one end secured to an eye- Ibolt 88 adjustablysecured'to the apertured end of lever 13 by nuts 8|. 'I'he opposite endof the spring 19 is elongated as at 82 and has the lateral end portion83 thereof seated in an elongated slot 8 4 in the o'set portion 85 oflever 66. This is adjacent the end of the lever which is slotted toreceive link 86 pivotally connected thereto as at 81. The other end oflink 86 is bifurcated and pivotally connects as at 88 to the rack bar 5|or an extension thereof.

Thev second form of the invention in addition to having thebasicoperating characteristics of the rst form does not include the stop48 because for vehicle use, to operate, the accelerator pedal would haveto be raised. For stopping the engine, therefore, there is provided aBowden wire 89, see Fig. 4, connected at one endr to pump rack shaft 5|as at 98 on lever 66-and its opposite end is positioned at a convenientlocation for the driver to pull upon. This accomplishes the same resultsas stop rod 31-see Figs. 1 and 2, because in this latter instance thelever I8, as a manual throttle, can be moved over center by hand whereaswith a foot throttle arrangement, such action is not desirable norusually provided since it requires a lifting effort.

This second form of the invention also has the advantage that it iscapable of foot operation without undue effort being required of the opverator of the vehicle.

Heretofore most governor equipped Diesel engine control have embodiedexcessive spring tensions requiring in turn such springs and alsosecuring a wider operating rangel with less tension on the maingoverning throttie-connected direct to a foot accelerator.

In Figs. '1 and 8 there is illustrated a further form of the inventionand similar tothat illustrated in Figs. 1 to 3, inclusive. Herein thecentrifugal operable mechanism disclosure has been omitted since it issubstantially the same as shown dotted in Figs. 4 and 6. The rock shaftI88,however, is rigid with lever |8| similar to lever 66 of Fig, 4 andlever 28 of Fig. l.

A segment support |82 pivotally supports throttle lever |83 at |84.Lever |83 yieldingly supports shoe |84 which rides in the groove- |85 ofthe support and'frictionally holds the lever in the hand adjustedposition. Abutment |85a is a lever stop.-

Lever also supports lug H5 apertured to re-v ceive eyebolt H6 lockedtherein by nuts H1 and extending toward lever |03. Lever |03 has agrooved pin extension H8 which is adjacent the pivot |04 of the lever|03 but upon the opposite side thereof relative to eyebolt |01. Minorspring H9 is connected ai; one end to eyebolt I6 at |6a and with someplay or lost motion as illustrated, if desired, and its opposite end iselongated at |20 to form an elongated open loop that is mounted in thegrooved portion of pin I8 thereby providing a lost motion connection.Lever |0| at |2| is adapted for connection to a Diesel engine pumprackbar.

In the form illustrated in Figs. 'I and 8, there are two levers and twosprings and each spring has a lost motion connection to one lever and anadjustable (rigid) connection to the other lever and each lever isrigidly connected to a spring, in this respect being similar to the formshown in Figs. 1 to 4, inclusive. K

In this form of the invention, see Figs. 7 and 8, neither spring iseffective upon shaft |00 while the other spring is effective thereon.Thus, the springs are'sequentially eiective upon shaft |00 throughmember |0|. The total range of movementof member 0| may be divided intoone portion wherein-only spring I4 is effective and another portionwherein only spring H9 is effective.

, The position of member |02 wherein one spring becomes ineffectiveafter having been previously effective upon member |0| and wherein theother spring, previously ineffective thereon, becomes effective formovement of memberI |0| in one direction and vice versa for movement inthe by each spring in succession and independently of the other springtime of application.

3. In a single governor structure for an engine, the combination of asingle centrifugal device, arm means tiltable by the device, a fuelcontrol means connected to the arm means remote from the tilting axisthereof, a main load spring connected to the arm means between thecontrol means connection thereto, and the tilting axis thereof, anauxiliary spring operatively connected at one end to the arm meansbetween the tilting axis thereof and the load spring connection to thearm means, the opposite end of the auxiliary opposite direction maybecalled the common po-v mediately becomes effective upon removal of theeffectiveness of the other spring.

This operation characteristic is common to all three forms of theinvention and all forms have common operation except as hereinbeforedifferentiated or as is obvious from an inspection of the drawingsillustrating the several specific differences.

The invention claimed is:

1. In a single governor structure for an engine, thefcombination of afuel controlling member, a single centrifugal device, manually operablemeans, and dual springs interconnected with the manually operable meansand member, each spring being operable upon said member and similarlyand successively relative to the other spring time of operation thereonand independ ent thereof forv full range control, andv opposed by saiddevice whereby dual governor results are obtainable from said 'singlecentrifugal device.

2. In a single governor structure for an engine, the combination of alever, a single centrifugal device connected thereto for lever movement,a manually operable means for moving the lever,

a pair of springs, and means operatively connecting said springs to themanually operable means and lever such that the lever is always springconstrained, said spring constraint being applied spring beingrelatively stationarily mounted, and

lever means pivotally supported between the springs and including amanually movable end and an oppositely directed extension to which theother end of the load spring is connected.

4. In a single governor structure, a single centrifugal device, armmeans tiltable by the device, a fuel control means connected to the armmeans remote from the tilting axis thereof, a main load spring connectedto the arm means between the control means connection thereto and thetilting axis thereof, lever means having a manually operable end, and anauxiliary spring operatively connected at one end to the arm meansbetween the tilting axis thereof and the load spring connection thereto,said lever means having an end Aextending oppositely from its axis andmanually operable end, the other end of the load spring being connectedto said lever means opposite end. the auxiliary spring opposite endbeing connected to the lever means opposite the load spring connectionthereto relative to the lever means pivotal axis, the pivotal axis ofthe lever means being positioned between the lever means-springconnections. y

5. A device as defined by claim 3, characterized by the arm means beingof dual character and by the addition of,A a link therebetween forsimul-l taneous and parallel arm movement, the auxiliary spring havingconnection with thearm closest to the lever means.

6. A device as defined by claim 3, characterized by the load springhaving a lost motion connection at one end and an adjustable connectionat the opposite end.

7. A device as defined by claim 3, characterized by the load springhaving a lost motion connection at one endand an adjustable connectionat the opposite end, the lost motion connection being to the arm meansandthe adjustable connection being to the lever means.

8. A device as defined by claim 3, characterized by the auxiliary springhaving a lost motion connection at one end and an adjustable connectionl 11. A device as defined by claim 3, characterized by the auxiliaryspring having a-lost motion connection at one end and an adjustableconnection at the opposite end, and the main load spring having similarconnections but reversely positioned.

12. A device as defined by claim 3, characterized by the addition of anelongated control rod carried by one of said means and slidablysupported-by, the other means, and stop means on said rod adjacent thelast mentioned means.

13. A device as defined by claim 3, characterized by the addition of amanually operable member connected to the arm meansfor cutoff purposes.

14. A device as dened by claim 3, characterized by the inclusion of amultiplying arrangement for relief of operator strain, said arrangementincluding a supplemental lever and link.

15. A device as dened by claim 2, characterized by the inclusion of amultiplying arrangement for relief of operator strain, said arrangementincluding a supplemental lever and link.

16. A device as dened by claim 4, characterized by Vthe auxiliary springconnection to the lever means being immediately adjacent the pivotalaxis of the lever means.

17. A device as defined by claim 3, characterized by the addition ofanother arm means to which the first mentioned end of the auxiliaryspring is connected, and a link between the two arm means for conjointoperation thereof.

NEEL M. MCCULLOUGH.

